In general, the present invention relates to a portable radio information terminal and a screen-scroll method. More particularly, the present invention relates to a portable radio information terminal for confirming that an electric wave received from a radio base station installed at a remote location is a message signal destined for the portable radio information terminal, for notifying the user of the received message signal in the form of sound, light, mechanical vibration or another form to make the user aware of the arrival of the message signal, for displaying a message conveyed in the signal on an embedded screen display unit and for scrolling the displayed screen in accordance with a command entered by the user. In particular, the present invention relates to a portable radio information terminal for carrying out radio communication of signals such as a pager and a pocket bell and relates to a screen-scroll method adopted in the portable radio information terminal.
A portable radio information terminal is a handy and portable apparatus that is capable of functioning as a terminal of a communication network. In recent years, there have been implemented portable radio information terminals with a variety of configurations and functions to meet a rapidly growing demand in a wide range of applications in the field of information communication.
An example of such a portable radio information terminal is a pager which is widely used for carrying out communications of radio signals.
An early pager generates bell sound when a calling signal is received from a radio base station. A radio calling signal is capable of calling the user carrying this pager even if the user is present at a separated place. The radio calling signal is normally used to urge the user to respond to the calling signal by using a wire telephone closest to the user.
A signal generated by the radio base station is not merely ended with such a calling signal. A signal generated by the radio base station is also capable of conveying information. On the pager side, on the other hand, information conveyed by an incoming signal is decoded and a result of the decoding is stored in a memory unit and displayed on a liquid-crystal display panel as a message. A pager having functions to decode, store and display such information has been developed and widely used at the present time.
In recent years, such a pager is further provided with a message notifying unit having a function of generating ringing sound of a bell to notify the user of an incoming message. While the ringing sound of a bell used as a message is an effective message notifying means, it is feared that the user can not hear the sound of the message or the calling sound in the event of an incoming call in some cases when the pager is used outdoors or at a trip destination or, in particular, in a noisy environment. At a place such as a movie theater or a lecture meeting place, on the other hand, there is not much noise. At such a place, however, message sound or calling sound will be a disturbance to the atmosphere. In order to solve the problems described above, the message notifying unit is generally designed into a configuration also including a vibration function of a vibrator for informing the user of a message by vibration in place of ringing sound of a bell. The configuration allows the user to manually operate an input device to select either ringing sound of a bell or vibration of a vibrator as a message-notification means.
The portable radio information terminal is provided with an input device for use by the user to specify an operating condition. In the conventional portable radio information terminal, the input device is usually a device of the key or button type.
However, a key-type or button-type input device is not always appropriate for a continuous input operation. That is to say, with such an input device, there is limitation on the continuous input operation. Moreover, each key or button has a unique function so that, in the case of a portable radio information terminal having more functions, the number of keys or buttons increases, making the operation complicated. As a result, there is raised a problem of a hindrance to efforts to make the portable radio information terminal smaller in size.
In order to solve the problems described above, there has been developed a rotary/press input device comprising a rotary input operation unit and a press switch built into a single assembly in place of the input device with the key or button type.
Such a rotary/press input device is put to practical use typically as a jog dial or a rotary encoder. The rotary input operation unit is implemented by a disc-shaped knob built into a single assembly with the press switch. The disc-shaped knob can be rotated in clockwise (right) and counterclockwise (left) directions with a high degree of freedom to generate a control signal with ease.
It is thus possible to carry out an operation to generate a plurality of input signals within a unit time with ease. In addition, since signals of 2 different types can be obtained from a single rotary/press input device, the space occupied by input devices can be reduced.
By the way, in an operation to display message information or a message text conveyed by an incoming signal, there is a limit on the number of lines of the message text that can displayed on the screen of the image displaying unit. Typically, only up to 4 lines of message information can be displayed. Thus, in the case of a message text composed of a number of lines, the user needs to carry out an operation to scroll up or down the message text in order to display all the lines sequentially.
In an operation to scroll up a displayed message text, the text is updated in the upward direction. In an operation to scroll down a displayed message text, on the other hand, the text is updated in the downward direction. It is desirable to allow the user to manually specify the number of lines by which the scroll operation is to be carried out and the direction as well as the speed of the scroll operation.
Particularly, in order to display a message text with a large number of lines, it is desirable to design a portable radio information terminal into a configuration wherein a command to perform a scroll operation can be carried out a plurality of times in a short period of time and, hence, a scroll processing function can be executed at a high speed.
Since the rotary input operation unit described above can be rotated at a high speed, a number of input signals can be generated in a unit time. Thus, such a rotary input operation unit is suitable for an operation to enter a command to scroll the screen. At least, the input operation can be carried out at a high speed.
However, while an input operation to scroll the displayed screen by a plurality of lines in a short period of time can be carried out, there is a problem caused of a hindrance to a fast response by the scroll processing function of the portable radio information terminal to follow such an input operation.
In order to scroll a displayed screen at a high speed, for example, a command to request a scroll operation is entered via the input unit continuously a plurality of times in a short period of time. A signal requesting a scroll operation is generated for each input operation. Thus, if 8 input operations are carried out consecutively in a short period of time, 8 signals each requesting a scroll operation are generated. As a result, a scroll operation by 1 line is carried out consecutively.
With the conventional technology, the image is just shifted by 1 line in each scroll operation. In addition, the shifted screen is displayed at the end of each scroll operation. In the above example, 8 screens are displayed sequentially before the series of scroll operations are completed
FIG. 16 is an explanatory diagram showing the conventional downward 1-line scroll processing. As shown in the figure, downward 1-line scroll processing is carried out consecutively 3 times on an initial screen image G140. At the end of the first scroll operation, data EE appears on the last line of the screen while top data AA disappears from the screen, resulting in a screen image G141. The second scroll operation results in a screen image G142 and the third scroll operation results in a screen image G143.
As described above, 3 new different screens are displayed in order to update the image G140 with the image G143.
FIG. 17 is an explanatory diagram showing the conventional upward 1-line scroll processing. As shown in the figure, upward 1-line scroll processing is carried out consecutively 3 times on an initial screen image G150. At the end of the first scroll operation, data KK appears on the first line of the screen while bottom data OO disappears from the screen, resulting in a screen image G151. Then, the second scroll operation results in a screen image G152 and the third scroll operation results in a screen image G153.
As described above, 3 new different screens are displayed in order to update the image G150 with the image G153.
If the processing speed of the image displaying unit and/or the peripheral circuit to update the screen displayed on the liquid-crystal display panel is low and/or there is a limit on the processing speed of the CPU, the scroll processing does not follow up operations carried out by the user to enter commands requesting scroll processing. In this case, the performance of the portable radio information terminal is limited by the processing speeds of the image displaying unit, the peripheral circuit and/or the CPU. Thus, since it takes time to complete an operation to update the screen which is carried out for each 1-line scroll operation, the scroll processing does not follow up the operations carried out by the user to enter the commands requesting the scroll processing in a short period of time. That is to say, there is a gap between the speed of the input operations carried out by the user and the speed of the scroll processing performed by the portable radio information terminal. As a result, there are raised a problem of impossible smooth processing and a problem that the user is not capable of operating the portable radio information terminal in a way the user likes.